/*
 * This file contains some defines for the floppy disk controller.
 * Various sources. Mostly "IBM Microcomputers: A Programmers
 * Handbook", Sanches and Canton.
 */
/* 本文件包含了关于软盘控制器的定义,此文参考了很多资料。
 * 参考最多的资料是 "IBM 迷你电脑:程序员手册", Sanches, Canton。*/
#ifndef _FDREG_H
#define _FDREG_H

extern int ticks_to_floppy_on(unsigned int nr);
extern void floppy_on(unsigned int nr);
extern void floppy_off(unsigned int nr);
extern void floppy_select(unsigned int nr);
extern void floppy_deselect(unsigned int nr);

/* Fd controller regs. S&C, about page 340 */
/* 软盘控制器寄存器,约在340页 */
#define FD_STATUS   0x3f4
#define FD_DATA     0x3f5
#define FD_DOR      0x3f2 /* Digital Output Register */
#define FD_DIR      0x3f7 /* Digital Input Register (read) */
#define FD_DCR      0x3f7 /* Diskette Control Register (write)*/

/* Bits of main status register */
#define STATUS_BUSYMASK 0x0F /* drive busy mask */
#define STATUS_BUSY  0x10    /* FDC busy */
#define STATUS_DMA   0x20    /* 0- DMA mode */
#define STATUS_DIR   0x40    /* 0- cpu->fdc */
#define STATUS_READY 0x80    /* Data reg ready */

/* Bits of FD_ST0 */
#define ST0_DS   0x03 /* drive select mask */
#define ST0_HA   0x04 /* Head (Address) */
#define ST0_NR   0x08 /* Not Ready */
#define ST0_ECE  0x10 /* Equipment chech error */
#define ST0_SE   0x20 /* Seek end */
#define ST0_INTR 0xC0 /* Interrupt code mask */

/* Bits of FD_ST1 */
#define ST1_MAM 0x01 /* Missing Address Mark */
#define ST1_WP  0x02 /* Write Protect */
#define ST1_ND  0x04 /* No Data - unreadable */
#define ST1_OR  0x10 /* OverRun */
#define ST1_CRC 0x20 /* CRC error in data or addr */
#define ST1_EOC 0x80 /* End Of Cylinder */

/* Bits of FD_ST2 */
#define ST2_MAM 0x01 /* Missing Addess Mark (again) */
#define ST2_BC  0x02 /* Bad Cylinder */
#define ST2_SNS 0x04 /* Scan Not Satisfied */
#define ST2_SEH 0x08 /* Scan Equal Hit */
#define ST2_WC  0x10 /* Wrong Cylinder */
#define ST2_CRC 0x20 /* CRC error in data field */
#define ST2_CM  0x40 /* Control Mark = deleted */

/* Bits of FD_ST3 */
#define ST3_HA 0x04 /* Head (Address) */
#define ST3_TZ 0x10 /* Track Zero signal (1=track 0) */
#define ST3_WP 0x40 /* Write Protect */

/* Values for FD_COMMAND */
#define FD_RECALIBRATE 0x07 /* move to track 0 */
#define FD_SEEK        0x0F /* seek track */
#define FD_READ        0xE6 /* read with MT, MFM, SKip deleted */
#define FD_WRITE       0xC5 /* write with MT, MFM */
#define FD_SENSEI      0x08 /* Sense Interrupt Status */
#define FD_SPECIFY     0x03 /* specify HUT etc */

/* DMA commands */
#define DMA_READ  0x46
#define DMA_WRITE 0x4A

#endif
